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normbac

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I am installing a 208 volt 3 phase panel 1000 ft from main panel it is for a 60 amp 3 phase motor load I was going to run paralell 4/0 AL question is 2/0 AL egc the correct size. Would it be a better design to just use a 4/0 as a neutral with no egc panel will be installed in a shipping container used for storage out in an open field. TIA
 
If you are past the service disconnect, there is no way you can avoid running both a grounded conductor (neutral) and an EGC.
If you are able to run a separate set of service conductors from the line side of the main disconnect you must run just a single grounded conductor.

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normbac said:
I am installing a 208 volt 3 phase panel 1000 ft from main panel it is for a 60 amp 3 phase motor load I was going to run paralell 4/0 AL question is 2/0 AL egc the correct size. Would it be a better design to just use a 4/0 as a neutral with no egc panel will be installed in a shipping container used for storage out in an open field. TIA
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If the load is only 3? couldn't you delete the neutral and just have an EGC?
 
normbac said:
I am installing a 208 volt 3 phase panel 1000 ft from main panel it is for a 60 amp 3 phase motor load I was going to run paralell 4/0 AL question is 2/0 AL egc the correct size. Would it be a better design to just use a 4/0 as a neutral with no egc panel will be installed in a shipping container used for storage out in an open field. TIA
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according to the southwire VD calculator

1 conductors per phase utilizing a #250 Aluminum conductor will limit the voltage drop to 4.95% or less when supplying 60.0 amps for 1000 feet on a 208 volt system.
For Engineering Information Only:
205.0 Amps Rated ampacity of selected conductor
0.09 Ohms Resistance (Ohms per 1000 feet)
0.041 Ohms Reactance (Ohms per 1000 feet)
10.4 volts maximum allowable voltage drop at 5%
10.275. Actual voltage drop loss at 4.95% for the circuit
0.9 Power Factor
Click to expand...

I don't think you need a N if it is not being used at the end but you do need an EGC.

Lots of wire. Have you considered running 480 to reduce the wire size instead of 208?
 
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petersonra said:
according to the southwire VD calculator



I don't think you need a N if it is not being used at the end but you do need an EGC.

Lots of wire. Have you considered running 480 to reduce the wire size instead of 208?
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Need minimum 200 volts at end so #250 would be an issue
Main panel is 120/208 so no 480 available
there are feed thru lugs off 200amp main
 
electrofelon said:
Wouldnt he want to consider the VD from the starting current, not just the FLA of the motor? There must be a "rule of thumb" for this? Like Petersonra said, maybe you should price out a 480 transformer on each end.
Click to expand...

Or put a 208/480V xfmr at the source and change the motor to be 480 at the other end.
 
2/0 is not the correct size for the EGC. A normal 60 amp would be #4 AL + #8 EGC. Since you are increasing
the conductor size from #4 AL to 2 - 4/0 AL, the EGC must be increased by the same percentage. It appears that
the EGC may require 2 - 4/0 AL. You need to check this out using the circular mils of the conductors.
 
bob said:
2/0 is not the correct size for the EGC. A normal 60 amp would be #4 AL + #8 EGC. Since you are increasing
the conductor size from #4 AL to 2 - 4/0 AL, the EGC must be increased by the same percentage. It appears that
the EGC may require 2 - 4/0 AL. You need to check this out using the circular mils of the conductors.
Click to expand...
you cannot use parallel conductors for the egc.
 
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